Rear Wiper Won't Turn Off

[The Grand Pooh-Bah]

2001 QX4
Had to pull the fuse. Where is the rear wiper relay located. Is this common?

[VStar650CL]

The QX4's have a Rear Wiper Controller (N/I calls it an "amplfier") located behind the lefthand luggage room trim. There are two possibilities, either the driver FET in the controller is blown or the auto-stop switch in the wiper motor isn't working. When the wiper is running you should see a low pulse on the WHT/BLK wire at the wiper motor each time it hits the stop position. If so, the controller is shot, if not, the motor is shot.

[mdmellott]

Not common. Definitely weird. No relay for this I am aware of. Check out pages EL-141 thru EL-146 for the schematics and operation description of this rear wiper. It might help you track down this anomaly.
https://www.nicoclub.com/service-manual ... System.pdf

[The Grand Pooh-Bah]

Thanks...I will check those possibilities out.

[The Grand Pooh-Bah]

https://www.youtube.com/watch?v=z0FNeSSkn9c

Here is a video of what my rear wiper is doing when it runs. It is going all the way to the resting bracket on each wipe. Also it never touches the micro switch. I can't see anything broken.

[The Grand Pooh-Bah]

I also discovered that the rear hatch glass power goes through the wiper motor. My rear glass electric hatch also does hot work. The clues are pointing towards the rear wiper motor.

[mdmellott]

There is a rear wiper amplifier assembly relay module (28510-3W400) that controls how and when the rear wiper and glass hatch works. This module is located behind the interior left rear side body panel in the cargo area. The electrical system service manual section describes the voltage readings you should get at the various terminal pins on this module, at different wiper control switch settings, to help with trouble diagnosis. To be honest, I read through all that in the service manual and it made my head hurt. I looked up the amplifier part number but found it to be a discontinued item. https://www.infinitipartsdeal.com/parts ... 5DE;3=USA) Hopefully, it's just a dirty multi-pin connector to this module that can be unplugged, cleaned up, and hope for a plug and play fix.

[VStar650CL]

It probably isn't the Amp, Md. The Amp relies on a "park" pulse from a switch inside the wiper motor to know where to stop the blade. If that switch fails the Amp will keep trying to park the arm, but of course it can't so it just keeps trying, looking for a pulse that won't ever come.

[mdmellott]

It probably isn't the Amp, Md. The Amp relies on a "park" pulse from a switch inside the wiper motor to know where to stop the blade. If that switch fails the Amp will keep trying to park the arm, but of course it can't so it just keeps trying, looking for a pulse that won't ever come.

Curious. Is that only when the control switch is turned off but the wiper just won't turn off? After looking at the video that was posted, I was thinking the wiper was running continuously to the park position while the control switch was turned on.

[VStar650CL]

Yep, the Amp will only look at the park signal when it's running intermittent or turned off. In continuous operation there's no need for it.

[The Grand Pooh-Bah]

It's fixed. I found that the orange wire at the wiper motor was unplugged. I plugged it back in and the wiper motor works perfectly and the rear glass hatch switch works.

Next on the list is the Valve Cover Gaskets.